Adjustment mechanism

ABSTRACT

An adjustment mechanism ( 20 ) for an article of furniture includes a support structure ( 22 ) securable to a seat base of the article of furniture. A carrier ( 24 ) is displaceably arranged relative to the support structure ( 22 ), the carrier ( 24 ) being configured to mount a component ( 12 ) of the article of furniture. A link assembly ( 26 ) interconnects the support structure ( 22 ) and the carrier ( 24 ). The link assembly ( 26 ) comprises at least one linkage mechanism ( 52 ) which causes initial, substantially linear motion of the carrier ( 24 ) relative to the support structure ( 22 ) to become substantially rotary motion as the carrier ( 24 ) moves from a first position to a second position relative to the seat base of the article of furniture.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from Australian Provisional Patent Application No. 2010903144 dated 14 Jul. 2010, the contents of which are incorporated herein by reference in its entirety.

FIELD

This disclosure relates, generally, to an article of furniture and, more particularly, to an adjustment mechanism for an article of furniture and to an article of furniture including the adjustment mechanism.

SUMMARY

An adjustment mechanism for an article of furniture includes

a support structure securable to a seat base of the article of furniture;

a carrier displaceably arranged relative to the support structure, the carrier being configured to mount a component of the article of furniture; and

a link assembly interconnecting the support structure and the carrier, the link assembly comprising at least one linkage mechanism which causes initial, substantially linear motion of the carrier relative to the support structure to become substantially rotary motion as the carrier moves from a first position to a second position relative to the seat base of the article of furniture.

The component of the article of furniture may be a backrest or an armrest of the article of furniture. While the adjustment mechanism has been designed specifically for an armrest of an article of furniture, such as a sofa, it will be appreciated that the adjustment mechanism could be used, without modification, with a backrest of the article of furniture. Further, the article of furniture need not be a sofa but could be an armchair, an outdoor lounger, or the like. For ease of explanation, the adjustment mechanism will be described with reference to its application in an armrest of the article of furniture.

The link assembly may be configured to cause the carrier to move substantially linearly initially and then, upon further displacement of the carrier relative to the support structure, to cause the carrier to pivot relative to the support structure to move the carrier from the first position to the second position and vice versa to move the carrier from the second position to the first position.

The at least one linkage mechanism may comprise a pair of spaced links, each link having a pair of spaced pivot points, a centre line passing through the pivot points of a first of the links being substantially parallel to a centre line passing through the pivot points of a second of the links when the carrier is in its first position relative to the support structure.

The links may be of unequal length with the spacing between the pivot points of the first link being greater than the spacing between the pivot points of the second link, the first link, in use, being operatively below the second link. A first pivot point of the first link may be aligned with a first pivot point of the second link in a direction in which the carrier is initially displaced relative to the support structure when moving the carrier from the first position to the second position. Thus, as the carrier is raised from its first position, the second pivot point of the first link scribes a greater arc than the second pivot point of the second link to achieve the combined linear and rotary motion of the carrier relative to the support structure to effect displacement of the carrier into its second position.

The first link may have a curved or substantially boomerang shape with a concavity of the first link facing towards the second link. The second link may be a substantially straight link.

The support structure may comprise a plurality of limbs. Each limb may be substantially L-shaped with one arm of the limb being kinked. The limbs may be interconnected by a bridging member.

The link assembly may include a plurality of linkage mechanisms and each of at least some of the limbs may carry a mounting formation for mounting one of the linkage mechanisms to the support structure. The links of each linkage mechanism may be connected to their associated mounting formation of the support structure by the first pivot points of the links.

The carrier may comprise at least one bracket to which the component of the article of furniture is attachable. More particularly, the carrier may comprise a plurality of brackets, each of which is associated with one of the limbs of the support structure. The second pivot points of the links of each linkage mechanism may connect the links to their associated bracket.

There is also disclosed an article of furniture which includes an adjustment mechanism as described above.

BRIEF DESCRIPTION OF DRAWINGS

In the drawings,

FIG. 1 shows a front view of an article of furniture incorporating an embodiment of an adjustment mechanism with a component of the article of furniture being in a first position;

FIG. 2 shows a front view of the article of furniture with the component of the article of furniture being in a second position;

FIG. 3 shows a schematic, part sectional side view of an embodiment of an adjustment mechanism, the adjustment mechanism carrying the component of the article of furniture with the component being shown in its first position;

FIG. 4 shows a schematic, part sectional side view of the adjustment mechanism, the adjustment mechanism carrying the component of the article of furniture with the component being shown in its second position;

FIG. 5 shows a perspective view of the adjustment mechanism;

FIG. 6 shows a perspective view of a support structure of the adjustment mechanism; and

FIG. 7 shows a perspective view of a bracket of a carrier of the adjustment mechanism.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the drawings, reference numeral 10 generally designates an embodiment of an article of furniture. In the described embodiment, the article of furniture is in the form of a sofa and the disclosure will be described with reference to its application to the sofa 10. It will, however, be appreciated that the disclosure is equally applicable to other articles of furniture such as, for example, an armchair, an outdoor lounger, or the like. In addition, the disclosure will be described with reference to its application to an armrest 12 of the sofa 10. It will be appreciated that the disclosure is equally applicable to the backrest of the sofa.

The sofa 10 comprises a pair of spaced armrests 12 extending upwardly from a seat base 14. The sofa 10 further includes a backrest (not visible) against which, in this embodiment, cushions 16 rest. The seat base 14 is supported on a plurality of legs 18.

At least one of the armrests 12, but preferably both armrests 12, incorporates an adjustment mechanism 20 (FIGS. 3-5). The adjustment mechanism 20 includes a support structure 22 securable to the seat base 14 of the sofa 10. A carrier 24 is displaceably arranged relative to the support structure 22. The carrier 24 carries the armrest 12. A link assembly 26 interconnects the support structure 22 and the carrier 24.

The support structure 22 comprises a plurality of spaced limbs 28. In the described embodiment, the support structure 22 comprises a pair of spaced limbs 28 (shown most clearly in FIG. 6 of the drawings). The limbs 28 are interconnected by a bridging portion in the form of a beam or bar 30. It will be appreciated that the support structure 22 could comprise more than two spaced limbs 28 or a single limb 28 of sufficient width to provide stability to the carrier 24.

Each limb 28 is substantially L-shaped having a first arm 32 and a second arm 34 projecting substantially at right angles from the first arm 32. The arm 32 has an opening 36 defined proximate its free end (as illustrated in FIGS. 3 and 4 of the drawings). The opening 36 receives a securing formation, such as a securing pin (not shown), for securing the limb 28 to a suitable part, such as an underside, of the seat base 14 of the sofa 10. If desired, the securing pin can be carried at an operatively upper end of the leg 18 to project into the seat base 14.

The arm 34 of each limb 28 is dog leg-shaped having a kink 38 formed in it. A mounting formation in the form of a mounting plate 40 is carried on the arm 34 operatively above the kink 38 and projecting in a direction opposite to that of the arm 32. The mounting plate 40 defines a pair of spaced openings 42 and 44. The openings 42 and 44 are generally aligned with each other in a substantially vertical orientation, in use.

The carrier 24 comprises a plurality of brackets 46. There are the same number of brackets 46 of the carrier 24 as there are limbs 28 of the support structure 22. Thus, in the described embodiment, there are two brackets 46, each bracket 46 being associated with one of the limbs 28 of the support structure 22. The brackets 46 of the carrier 24 mount a frame 48 of the armrest. Conveniently, the frame 48 of the armrest 12 is welded to the brackets 46 of the carrier 24. However, it will be appreciated that the frame 48 could, instead, be secured to the brackets 46 by fasteners such as screws, rivets, or the like. It will also be appreciated that, if the support structure 22 comprises a single limb 28, two brackets 46 could be associated with the limb 28 being mounted on opposite sides of the limb 28.

An example of the bracket 46 is shown more clearly in FIG. 7 of the drawings. The bracket 46 defines a pair of spaced openings 49 and 50. Unlike the openings 42 and 44 of the mounting plates 40 of the support structure 42, the openings 49 and 50 of the bracket 46 are out of alignment with each other, relative to a vertical axis, when the bracket 46 is substantially vertically orientated, in use.

The link assembly 26 comprises a linkage mechanism 52 associated with each limb 28 of the support structure 22 and each associated bracket 46 of the carrier 24. More particularly, each linkage mechanism 52 mounts one of the brackets 46 to the mounting plate 40 of one of the limbs 28.

Each linkage mechanism 52 comprises a pair of spaced links 54 and 56 with the link 56 being arranged operatively above the link 54. The links 54 and 56 are of unequal length with the link 54 being longer than the link 56.

When viewed side on, as in FIG. 3 of the drawings, the first link 54 is substantially curved or boomerang-shaped having a concavity 58 facing towards the second link 56. When viewed side on, the second link 56 is a substantially straight link. The link 54 has a pair of spaced openings 60 and 62. The link 54 is secured to the mounting plate 40 via a pivot pin 64 received through the opening 60 of the link 54 and the opening 42 of the mounting plate 40.

A pivot pin 66 is received through the opening 62 of the link 54 and the opening 49 of the bracket 46 to secure the link 54 to the bracket 46.

The link 56 defines a pair of spaced openings 68 and 70. A pivot pin 72 is received through the opening 68 of the link 56 and the opening 44 of the mounting plate 40 for securing the link 56 to the mounting plate 40. A pivot pin 74 is received through the opening 70 of the link 56 and the opening 50 of the bracket 46 for securing the link 56 to the bracket 46.

A centre line passing through the centres of the pivot pins 64 and 66 received in the openings 60 and 62 of the first link 54, respectively, is substantially parallel to a centre line passing through the centres of the pivot pins 72 and 74 received in the openings 68 and 70 of the second link 56, respectively, when the armrest 12 is in its first position as shown in FIGS. 1 and 3 of the drawings.

It is also to be noted that the spacing between the pivot pins 64 and 66 associated with the link 54 is greater than the spacing between the pivot pins 72 and 74 associated with the link 56. The links 54 and 56 pivot about the pivot pins 64 and 72, respectively, with the pivot pin 66 scribing a greater arc than the pivot pin 74.

As shown most clearly in FIG. 5 of the drawings, both links 54 and 56 are cranked, at 76 and 78, respectively, to facilitate spacing of the bracket 46 from the arm 34 of the limb 28 of the support structure 22 and also to allow the link 54 to pivot relative to the link 56. It is to be noted that, in FIG. 5 of the drawings, the pivot pins are omitted.

To move the armrest 12 from the first position shown in FIGS. 1 and 3 of the drawings, to the second position as shown in FIGS. 2 and 4 of the drawings; the armrest 12 is, initially, raised in the direction of arrow 76 (FIG. 3). The links 54 and 56 pivot about their associated pivot pins 64 and 72 but, due to the difference in the lengths of the links 54 and 56, the initial movement of the armrest 12 is substantially vertically upward relative to the support structure 22 and, accordingly, the seat base 14 of the sofa 10. This substantially vertical movement of the armrest 12 relative to the seat base 14 only occurs for a relatively short distance to enable the bottom of the armrest 12 to clear the top of the seat base 14. Further movement of the links 54 and 56 about their pivot pins 64 and 72, respectively, results in the armrest 12 tilting outwardly due to the links 54 and 56 pivoting about their pivot pins 64 and 72, respectively. At the limit of movement of the links 54 and 56, the armrest 12 adopts the position shown in FIGS. 2 and 4 of the drawings. In this position, an inner, lower corner 78 (FIG. 2) of the armrest 12 is substantially in register with an upper, outer corner 80 of the seat base 14 of the sofa 10. Thus, an operatively inner surface 82 of the armrest 12 forms a substantially continuous (i.e. unbroken) surface with an operatively upper surface 84 (FIG. 2) of the seat base 14.

A user of the sofa 10 can then use the angled armrest 12 to rest against in a reclining position. In addition, for shorter sofas, the armrest 12, when in the second, angled position, as shown in FIGS. 2 and 4 of the drawings, forms an extension of the seat base 14 to enable the sofa 10 to be used as a bed.

It will be appreciated that, both in the first position and in the second position, the armrest 12 is retained in that position under the effect of gravity and no retention mechanisms are required to keep the armrest 12 either in its first position or its second position. Friction between the armrest 12 and the seat base 14 further assists in retaining the armrest 12 in position, particularly in its first position, relative to the seat base 14.

It is an advantage of the described embodiment that an adjustment mechanism 20 is provided which facilitates adjustment of the position of a component 12 of an article of furniture 10 relative to the remainder of the article of furniture 10. The adjustment mechanism 20 is compact and is hidden in the component 12 to be adjusted thereby enabling a slim, elegant article of furniture to be formed. Despite being compact, the adjustment mechanism 20 is robust rendering it suitable for repeated use. As there are no externally visible parts, an article of furniture incorporating the adjustment mechanism 20 is also rendered more aesthetically pleasing.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the disclosure as shown in the specific embodiments without departing from the scope of the disclosure as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. 

1. An adjustment mechanism for an article of furniture, the adjustment mechanism including a support structure securable to a seat base of the article of furniture; a carrier displaceably arranged relative to the support structure, the carrier being configured to mount a component of the article of furniture; and a link assembly interconnecting the support structure and the carrier, the link assembly comprising at least one linkage mechanism which causes initial, substantially linear motion of the carrier relative to the support structure to become substantially rotary motion as the carrier moves from a first position to a second position relative to the seat base of the article of furniture.
 2. The adjustment mechanism of claim 1 in which the link assembly is configured to cause the carrier to move substantially linearly initially and then, upon further displacement of the carrier relative to the support structure, to cause the carrier to pivot relative to the support structure to move the carrier from the first position to the second position and vice versa to move the carrier from the second position to the first position.
 3. The adjustment mechanism of claim 1 in which the at least one linkage mechanism comprises a pair of spaced links, each link having a pair of spaced pivot points, a centre line passing through the pivot points of a first of the links being substantially parallel to a centre line passing through the pivot points of a second of the links when the carrier is in its first position relative to the support structure.
 4. The adjustment mechanism of claim 3 in which the links are of unequal length with the spacing between the pivot points of the first link being greater than the spacing between the pivot points of the second link, the first link, in use, being operatively below the second link.
 5. The adjustment mechanism of claim 4 in which a first pivot point of the first link is aligned with a first pivot point of the second link in a direction in which the carrier is initially displaced relative to the support structure when moving the carrier from the first position to the second position.
 6. The adjustment mechanism of claim 1 in which the support structure comprises a plurality of limbs.
 7. The adjustment mechanism of claim 6 in which each limb is substantially L-shaped with one arm of the limb being kinked.
 8. The adjustment mechanism of claim 6 in which the limbs are interconnected by a bridging member.
 9. The adjustment mechanism of claim 6 in which the link assembly includes a plurality of linkage mechanisms and in which each of at least some of the limbs carries a mounting formation for mounting one of the linkage mechanisms to the support structure.
 10. The adjustment mechanism of claim 6 in which the carrier comprises at least one bracket to which the component of the article of furniture is attachable.
 11. The adjustment mechanism of claim 10 in which the carrier comprises a plurality of brackets, each of which is associated with one of the limbs of the support structure.
 12. An article of furniture which includes an adjustment mechanism as claimed in claim
 1. 